Carbon monoxide air exchange system

ABSTRACT

An air exchange system for use in commercial and residential buildings for monitoring the concentration of carbon monoxide or other gaseous components of air present in the building, and for removing the carbon monoxide from the air upon reaching a predetermined threshold concentration. The system utilizes standard carbon monoxide detectors located in rooms on all floors of the building which are electrically connected to a central control unit. When an excessive level of carbon monoxide is detected by one or more of the detectors, the control unit triggers shut-down of all potential sources of carbon monoxide within the building. The control unit simultaneously reverses the flow of air through the central heating/air conditioning system to remove the ambient room air and any carbon monoxide present at floor level and vents the room air to the outside of the building while bringing fresh air into the building. Audible and visual alarms sound to warn persons within the building that an undesirable level of carbon monoxide has been detected and that the ventilation mode has started.

RELATED APPLICATION

[0001] This application claims priority of my copending U.S. Provisional Patent Application No. 60/286,266 filed Apr. 24, 2001, the disclosure of which is herein incorporated by reference.

BACKGROUND OF THE INVENTION

[0002] 1. Field

[0003] The present invention relates to carbon monoxide safety systems for use in buildings, and more specifically to those safety systems which detect excessive levels of carbon monoxide, provide a warning signal to persons in the building of the excessive level of carbon monoxide, and automatically begin ventilation of the carbon monoxide from within the building.

[0004] 2. State of the Art

[0005] Carbon monoxide poisoning is a common and a serious hazard which accounts for numerous deaths each year. The seriousness of the hazard relates to the colorless and odorless nature of carbon monoxide so it cannot be detected by persons. Carbon monoxide is strongly attracted to hemoglobin within the blood which normally carries oxygen from the lungs throughout the body. Carbon monoxide displaces the oxygen within the blood and can cause rapid unconsciousness with little or no warning.

[0006] Carbon monoxide is a by-product of incomplete combustion such as wherein insufficient oxygen is present during combustion. Carbon monoxide may be produced by automobiles, furnaces, gas ranges and water heaters, wood burning fireplaces, charcoal grills, lawn mowers, and other gasoline engine driven equipment. The problem is most severe in confined spaces, such as in buildings, wherein the carbon monoxide builds to high enough concentrations to cripple or kill persons. The problem in buildings is compounded by the increasing lack of ventilation within newer buildings due to concern for energy efficiency. The likelihood of carbon monoxide poisoning decreases as the flow of fresh outside air increases so as to dilute and exhaust the carbon monoxide. Carbon monoxide poisoning a bigger problem during the winter months when gas fired heating systems are used to heat buildings.

[0007] Electronic detectors are most often used to detect excessive levels of carbon monoxide, particularly in homes. Such detectors provide a warning such as sounding an alarm or flashing a light when excessive levels of carbon monoxide are detected. These detectors are typically plugged into a wall outlet close to the floor in areas to be monitored, or wired into home security systems.

[0008] While the electronic detectors are useful to warn the occupants of the homes of excessive levels of carbon monoxide, those plugged directly into the electrical outlets are not monitored by a security company and are of little value such as to protect pets when the occupants are out. Additionally, occupants might be asleep and not hear the warning of the detector. Therefore, various systems have been devised in an attempt to remedy such a situation, such as by automatically shutting off the furnace producing the carbon monoxide, or automatically opening a garage door when the level of carbon monoxide becomes excessive.

[0009] In U.S. Pat. No. 5,576,739 issued to Murphy is disclosed a system for measuring noxious gas concentration in an affected area, and for controlling the device producing the noxious gas or for decreasing the concentration of the gas in the affected area. The system is primarily designed for detecting the concentration of carbon monoxide a garage area and for automatically opening the garage door using a garage door opener in response to a detected excessive level of carbon monoxide. The system is also described as able to turn off a furnace in response to the excessive level of carbon monoxide.

[0010] In U.S. Pat. No. 5,941,699 issued to Abele is disclosed a shutoff device for use with gas fired appliances which includes a sensor with associated thermocouple and conventional solenoid shutoff valve. The device is mounted close to the flame of the appliance to monitor the temperature of the flame. Slight changes in current from the thermocouple resulting from temprature variations of the flame monitored by the thermocouple provide an indication of increased carbon monoxide levels. The device may also be mounted in the plenum to monitor the temperature of primary and/or secondary screens associated with the gas fired appliance.

[0011] In U.S. Pat. No. 6,102,793 issued to Hansen is disclosed a ventilation system connected to a source of power for sensing an undesirable characteristic of air within an enclosed area monitored by the system, and for exchanging the air within the enclosed area with fresh air upon sensing the characteristic. The ventilation system includes at least one sensor for sensing the undesirable characteristic of the air within the enclosed area and comparing the characteristic to predetermined limit values, and a fan for ventilating the enclosed area. Upon determination by the sensors that the characteristic of the sensed air exceeds the predetermined limit, the fan is activated to replace the air within the enclosed area with fresh air. The sensor may sense heat, smoke, carbon dioxide, carbon monoxide, hydrogen sulfide, hydrogen cyanide, any detectable gas, or any other emergency condition, or any combination thereof. The fan is positioned within an air duct in the enclosed area which leads to a position outside the enclosed area. The system also includes a reset button connected to selectively disconnect the fan from the electrical power source.

[0012] In U.S. Pat. No. 6,110,038 issued to Stem is disclosed a system for detecting and purging carbon monoxide from a confined space such as a parking garage. The system includes a plurality of carbon monoxide detectors which provide a detection signal if a threshold level of carbon monoxide is detected. An activation circuit receives the detection signal from one or more of the detectors and provides an exhaust fan activation signal. A motor starter receives the exhaust fan activation signal, and electrical power so that when the exhaust fan activation signal is received from the activation circuit, the motor is started to purges the carbon monoxide from the space.

[0013] While the above described devices and systems may provide some advantages over the electronic detectors which plug into electrical outlets, there is a need for a comprehensive system for residential and commercial buildings.

SUMMARY OF THE INVENTION

[0014] The present invention are air exchange systems for use in buildings for monitoring the concentration of at least one gaseous component of air present in the building and for removing the gaseous component from the air upon reaching a predetermined threshold concentration.

[0015] A first version air exchange system is for use with a forced air system within a building. The forced air system is of the type having a blower unit which moves air from an inlet to an outlet thereof, an intake duct assembly thereof being connected to the inlet for gathering air from above a floor of the building, and an outlet duct assembly thereof connected to the outlet for distributing the air back throughout the building. The air exchange system is for monitoring the concentration of at least one gaseous component of air present in the building and for removing the gaseous component from the air upon reaching a predetermined threshold concentration. The air exchange system includes at least one detector which detects the level of the gaseous component, generating an alarm signal upon the level of the gaseous component reaching the predetermined threshold concentration. An exhausting unit has an upright housing which includes an internal chamber extending therethrough. The housing has an exhaust air inlet disposed above the floor and an exhaust air outlet adapted to discharge air externally of the building. A blower is operatively associated with the housing for moving air inside the building into the exhaust air inlet and out of the building through the exhaust air outlet. An inlet air duct assembly includes an inlet air duct having a fresh air inlet adapted to receive fresh air external of the building, and a fresh air outlet internal to the building. A normally closed bypass air valve is disposed along the inlet air duct. An electrical control system is operatively connected to each of the detectors for receiving the alarm signal and activating the blower to remove air from within the building by opening the bypass air valve to replenish removed air through the inlet air duct with fresh air from outside the building.

[0016] A second version air exchange system is for use in buildings to monitor and the concentration of at least one gaseous component of air present in the building, and remove the gaseous component from the air upon reaching a predetermined threshold concentration. The air exchange system includes at least one detector which detects the level of the gaseous component, generating an alarm signal upon the level of the gaseous component reaching the predetermined threshold concentration. An exhausting unit has an upright housing which includes an internal chamber extending therethrough, an exhaust air inlet disposed above the floor, and an exhaust air outlet adapted to discharge air externally of the building. A blower is operatively associated with the housing for moving air inside the building into the exhaust air inlet, and out of the building through the exhaust air outlet. An inlet air duct assembly includes an inlet air duct having a fresh air inlet adapted to receive fresh air external of the building and a fresh air outlet internal to the building. A normally closed bypass air valve is disposed along the inlet air duct. An electrical control system is operatively connected to each of the detectors for receiving the alarm signal and activating the blower to remove air from within the building, and opening the bypass air valve to replenish removed air through the inlet air duct with fresh air from outside the building.

[0017] A third version air exchange system is for use with a forced air system within a building. The forced air system is of the type having a blower unit which moves air from an inlet to an outlet thereof. An intake duct assembly is connected to the inlet for gathering air from the building, and an outlet duct assembly is connected to the outlet for distributing the air back throughout the building through a plurality of floor registers disposed closely adjacent a floor thereof. The air exchange system is for monitoring the concentration of at least one gaseous component of air present in the building, and removing the gaseous component from the air upon reaching a predetermined threshold concentration. The air exchange system includes at least one detector which detects the level of the gaseous component, generating an alarm signal upon the level of the gaseous component reaching the predetermined threshold concentration. An inlet air duct assembly includes an inlet air duct having a fresh air inlet adapted to receive fresh air external of the building, and a fresh air outlet connected to the intake duct assembly. A normally closed bypass air valve is disposed along the inlet air duct. An outlet duct assembly includes an outlet air duct having an exhaust air inlet for receiving air from within the building and an exhaust air outlet for discharging the air externally of the building. A valve assembly is operatively associated with at least one of the inlet and outlet duct assemblies to normally block fresh air from flowing through the fresh air inlet into the building, and air inside the building from flowing out through the outlet air duct to outside of the building. An electrical control system is operatively connected to each of the detectors for receiving the alarm signal and activating reversing the blower, and activating the valve assembly from a normally blocked position to a reversed position to reverse the flow of air. The air is drawn from inside the building through the floor registers and blown out through the outlet duct assembly, and fresh air drawn from outside the building through the inlet air duct assembly to replenish removed air.

THE DRAWINGS

[0018] The best mode presently contemplated for carrying out the invention is illustrated in the accompanying drawings, in which:

[0019]FIG. 1A is a top plan view of a commercial building having installed respective first and second exemplary carbon monoxide air exchange systems in accordance with the present invention, the first air exchange system shown being used with a roof mounted HVAC unit and shown in a normal mode of operation, and the second air exchange system being for stand-alone, non-HVAC use in a garage area;

[0020]FIG. 1B, a top plan view of the commercial building with the first and second air exchange systems in the ventilating mode of operation;

[0021]FIG. 2A, a longitudinal vertical sectional view of the commercial building taken on the line 2A-2A of FIG. 1A;

[0022]FIG. 2B, a longitudinal vertical sectional view of the commercial building taken on the line 2B-2B of FIG. 1B;

[0023]FIG. 3A, a top plan view of a residential building having installed a third exemplary carbon monoxide air exchange system in accordance with the present invention, the third air exchange system shown being used with a basement mounted HVAC unit and shown in a normal mode of operation;

[0024]FIG. 3B, a top plan view of the residential building with the third air exchange system in the ventilating mode of operation;

[0025]FIG. 4A, a longitudinal vertical sectional view of the residential building taken on the line 4A-4A of FIG. 3A;

[0026]FIG. 4B, a longitudinal vertical sectional view of the residential building taken on the line 4B-4B of FIG. 3B;

[0027]FIG. 5A, a lateral vertical sectional view of the residential building shown with the third air exchange system in the normal mode of operation;

[0028]FIG. 5B, a lateral vertical sectional view of the residential building shown with the third air exchange system in the ventilating mode of operation;

[0029]FIG. 6, a top plan view of the commercial building with a water sprinkler system for use with the carbon monoxide air exchange systems; and

[0030]FIG. 7, a schematic diagram of the electrical control system used in the air exchange systems.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

[0031] Referring to FIGS. 1A, 1B, 2A, and 2B, therein is shown respective first and second exemplary carbon monoxide air exchange systems in accordance with the present invention, designated generally at 20 and 23, as installed in a commercial building 26.

[0032] The air exchange system 20 comprises a plurality of carbon monoxide (CO) detectors 29, an exhausting unit 32, an inlet air louver valve 35, a bypass air louver valve 36, and an electrical control system 38. The air exchange system 20 connects to a standard heating, ventilating, and air conditioning (HVAC) system 41 which includes a heating/cooling HVAC unit 44 (shown roof-mounted), an intake duct assembly 47, and an outlet duct assembly 50. A gas inlet pipe 51 feeds propane or natural gas through a solenoid gas shutoff valve 52 for providing auxiliary heat to HVAC unit 44 in cold weather. The HVAC system 41 conditions the air by heating or cooling to a comfortable temperature within a plurality of rooms 53, 56, 59, 62, and 65 of building 26. A garage 68 is not connected to HVAC system 41. The HVAC system 41 draws air through an air return grill 71 and an air return duct 74 of intake duct assembly 47 which is mounted to a ceiling 48 of building 26, leading to an inlet 77 of HVAC unit 44. The air is heated or cooled in the standard way within HVAC unit 41, depending on the needs within building 26 as detected by a wall-mounted thermostat (not shown) mounted therein. The conditioned heated or cooled air returns to rooms 53, 56, 59, 62, and 65 through the ceiling 48 via a main return duct 80 which leads to a plurality of side return ducts 83 and an end return duct 86 of the outlet duct assembly 50.

[0033] The carbon monoxide (CO) detectors 29 are mounted on respective walls 89, 92, 95, 98, and 101 of building 26 closely adjacent a floor 104 thereof. The low positioning of detectors 29 permits the early detection of carbon monoxide, which is heavier than air and thus tends to accumulate near the floor 104. An electrical cable 107 extends from each detector 29 to the electrical control system 38. The exhausting unit 32 includes an upright housing 110 mounted to a wall 113 of building 26 which extends from the floor 104 through an upper ducting space 116 between the ceiling 48 and a flat roof 119 of building 26, extending outwardly from roof 119. The housing 110 includes an elongate internal chamber 122 extending the length thereof with an exhaust air inlet 125 disposed closely adjacent floor 104, and a capped exhaust air outlet 128 disposed above the roof 119. A blower 131 such as of the centrifugal type is mounted to a transverse baffle plate 134 disposed within chamber 122, dividing chamber 122 into respective upper and lower chambers 137 and 140 connected by a blower mounting hole (not shown) through which blower 131 moves air from the lower chamber 140 into the upper chamber 137. A normally closed louver assembly 143 covers exhaust air inlet 125 and includes a frame 146 having a plurality of transverse, inwardly extending, pivoting louvers 149. The louvers 149 are disposed in a generally vertical overlapping position when blower 131 is off, and move to a generally horizontally disposed position when blower 131 is on as pressure within building 26 exceeds that within chamber 122. Air moved through chamber 122 exhausts through capped exhaust air outlet 128, which comprises a plurality of outlet holes 152 covered from the weather by a pyramidal shaped cap 155.

[0034] The inlet air louver valve 35 is attached along air return duct 74 and includes a frame 158 which connects respective upper and lower air return duct portions 161 and 164 of air return duct 74. Inlet air louver valve 35 has a plurality of transverse pivoting louvers 167 which are synchronized to pivot together and which are spring-biased to an open position which allows air to flow through air return duct 74. An electric actuator (not shown) is operatively connected to the louvers 167 to move them to a closed position wherein no air flow is allowed through air return duct 74.

[0035] The bypass air louver valve 36 is attached to the upper air return duct portion 161 at a bypass air inlet hole 170 therethrough for drawing fresh air from outside of building 26. The bypass air louver valve 36 includes a frame 173 disposed about bypass air inlet hole 170, and a plurality of transverse pivoting louvers 176 which are synchronized to pivot together and which are spring-biased to a closed position which blocks fresh air from flowing through bypass air inlet hole 170 into air return duct 74. An electric actuator (not shown) is operatively connected to the louvers 176 to move them to an open position wherein fresh air flow from outside of building 26 is allowed into air return duct 74.

[0036] Referring to FIG. 7, the electrical control system 38 includes a control box 179 having a housing 182 which is mounted to the upright housing 110 of exhausting unit 32, and an electrical control assembly 185 located within the housing 182. The control assembly 185 comprises a 110 volt, 60 cycle (110 VAC) to 12 VAC power supply transformer 188, a barrier strip or electrical bus 191, and a relay module 194, all mounted to the housing 182. Externally supplied 110 volt 60 cycle electrical main power (110 VAC) from building 26 is input to control assembly 185 at respective positive and negative terminals 197 and 200. A reset switch 203 controls the main power to control assembly 185, with an indicator light 206 illuminating when the main electrical power is on. Reset switch 203 is used to manually reset control assembly 185 following detection of carbon monoxide. A capacitor 212 and a pair of diodes 213 and 214 are connected to electrical bus 191, a sensor input connector 215 connects to respective positive and negative terminals 218 and 221 of control assembly 185, and a plurality of output wires 224 and 227 extend from respective positive and negative terminals 230 and 233 of control assembly 185.

[0037] The detectors 29 comprise standard type electronic carbon monoxide detectors 236 which plug into an electrical outlet (not shown) supplying 110 VAC power. The detectors 236 include a detector device 239 connected to a warning output device 242 typically in the form of a speaker, buzzer, or light, by a pair of alarm output leads 245 and 248 which when activated are typically at an output voltage of about 32-34 volts. The modification comprises a pair of alarm output wires 251 and 254 of electrical cable 107 which tap into the respective alarm output leads 245 and 248, extending through a sheath 257 to a connector 258 adapted to receive electrical cables 107 from all of the detectors 29 and mate with connector 215 to merge all alarm signals transmitted therethrough into respective positive and negative components input at terminals 218 and 221. A diode 259 is disposed along each alarm output wire 251 to prevent the alarm signal of any of detectors 29 from sounding an audible or visual alarm on the other detectors 29. A plurality of output cables 260 connect electrical control assembly 185 to the inlet air louver valve 35, the bypass air louver valve 36, the blower 131, a warning device 261 such as an audio alarm or strobe light, and to gas shutoff valve 52.

[0038] When a detector 29 senses carbon monoxide at a predetermined level, the alarm signal sent from the particular detector 29 through the associated electrical cable 107 causes control assembly 185 to send the appropriate signals to the inlet air louver valve 35, the bypass air louver valve 36, blower 131 of exhausting unit 32, warning device 261, and gas shutoff valve 52. These signals cause simultaneous shutting off of the gas flow to the HVAC unit 44 which might be the source of the carbon monoxide, the changing of the air flow within building 26 from that indicated by arrows “A” to that indicated by arrows “B” to remove the carbon monoxide from within building 26, and the activation of warning device 261 to warn occupants of the detected carbon monoxide.

[0039] Again referring to FIGS. 1A, 1B, 2A, and 2B, the second exemplary carbon monoxide air exchange system 23 comprises a carbon monoxide (CO) detector 29, an exhausting unit 263, an inlet air louver valve 266, and electrical control system 38. The air exchange system 23 typically, though not necessarily, does not connect to the (HVAC) system 41, but rather is acts as a stand-alone system which operates only when an excessive level of carbon monoxide is detected in the garage 68.

[0040] The carbon monoxide (CO) detector 29 is mounted on a wall 272 closely adjacent a garage floor 275 thereof. The low positioning of detector 29 permits the early detection of carbon monoxide which tends to accumulate near the floor 275. Detector 29 or another detector 29 could be mounted on a wall 278 opposite a garage door 281 of garage 68. The electrical cable 107 extends from detector 29 to electrical control system 269. The exhausting unit 263 is similar to exhausting unit 32, including an upright housing 284 of the same cross-section as housing 110 but shorter in height is mounted to a wall 287 of garage 68 which extends from the floor 275 through the upper ducting space 116 between the ceiling 48 and the flat roof 119 of building 26, but stopping short of extending outwardly from roof 119. The housing 284 includes an elongate internal chamber 290 extending the length thereof with an exhaust air inlet 293 disposed closely adjacent floor 275, and a capped exhaust air outlet 296 extending outwardly through wall 287 externally of building 26. The same centrifugal blower 131 and transverse baffle plate 134 are disposed within chamber 290, dividing chamber 290 into respective upper and lower chambers 299 and 302 connected by the blower mounting hole (not shown) through which blower 131 moves air from the lower chamber 302 into the upper chamber 299. The normally closed louver assembly 143 covers exhaust air inlet 293 mounted thereto by frame 146. The louvers 149 thereof operate as previously described, moving from a generally vertical overlapping position when blower 131 is off to a generally horizontally disposed position when blower 131 is on. Air moved through chamber 290 exhausts through capped exhaust air outlet 296, which comprises an end wall 305, an outlet hole 308, and an outlet duct 311 extending outwardly through wall 287 externally of building 26. A louver 149 attached to outlet duct 311 at an outside surface 314 of wall 287 keeps rain and snow from entering exhausting unit 263.

[0041] The inlet air louver valve 266 is attached at an air inlet 317 through wall 272 closely adjacent ceiling 48 for drawing fresh air from outside of building 26. The inlet air louver valve 266 includes a frame 320 which extends through wall 272, and a plurality of transverse pivoting louvers 323 which are synchronized to pivot together and which are spring-biased to a closed position which prevents fresh air from flowing through air inlet 317. An electric actuator (not shown) is operatively connected to the louvers 323 to move them to an open position wherein fresh air flow is allowed through bypass air inlet 317.

[0042] When a detector 29 senses carbon monoxide at a predetermined level, the alarm signal sent from the particular detector 29 through the associated electrical cable 107 causes control assembly 185 to send the appropriate signals to the inlet air louver valve 266, blower 131 of exhausting unit 263, the warning device 261, and gas shutoff valve 52. These signals cause simultaneous shutting off of the flow to the HVAC unit 44 which might be the source of the carbon monoxide, the changing from no air flow within garage 68 to that indicated by arrows “C” to remove the carbon monoxide from within garage 68, and the activation of warning device 261 to warn occupants of the detected carbon monoxide.

[0043] Referring to FIGS. 3A, 3B, 4A, 4B, 5A, and 5B therein is shown a third exemplary carbon monoxide air exchange system in accordance with the present invention, designated generally at 326, as installed in a residential building 329.

[0044] The air exchange system 326 comprises a plurality of carbon monoxide (CO) detectors 29, an inlet air duct assembly 332, an outlet duct assembly 335, a bypass air louver valve 336, and electrical control system 38. The air exchange system 326 connects to a standard heating, ventilating, and air conditioning (HVAC) system 341 which includes a heating/cooling HVAC unit 344 (shown basement-mounted), an intake duct assembly 347, and an outlet duct assembly 350. A gas inlet pipe 351 feeds propane or natural gas through solenoid gas shutoff valve 52 for providing auxiliary heat to HVAC unit 344 in cold weather. The HVAC system 341 conditions the air by heating or cooling to a comfortable temperature within a plurality of rooms 353, 356, 359, 362, and 365 of building 329. A garage (not shown) may be also be connected to HVAC system 341. The HVAC system 341 draws air (FIGS. 3A, 4A, and 5A at arrows “G”) through a pair of centrally disposed air return grills 368 and air return ducts 371 and 374 to a main air return duct 377 of inltake duct assembly 347 which extend under a floor 380 of building 329, leading to an inlet 383 of HVAC unit 344. The air is heated or cooled in the standard way within HVAC unit 344, depending on the needs within building 329 as detected by a wall-mounted thermostat (not shown) mounted therein. The conditioned heated or cooled air returns to rooms 353, 356, 359, 362, and 365 through floor 380 via a main return duct 386 which leads to a plurality of side return ducts 389 and an end return duct 392 of the outlet duct assembly 350 terminating at respective floor registers 395.

[0045] The carbon monoxide (CO) detectors 29 are mounted on respective walls 398, 401, 404, 407, and 410 of building 329 closely adjacent the floor 380 thereof. The low positioning of detectors 29 permits the early detection of carbon monoxide which thus tends to accumulate near the floor 380. Electrical cable 107 extends from each detector 29 to the electrical control system 338. The inlet air duct assembly 332 includes an upright tube 413 which extends from the main air return duct 377 through floor 380, through an upper attic space 416 between a ceiling 419 and a sloped roof 422 of building 329, extending outwardly from roof 422. Upright tube 413 includes a capped exhaust air outlet 425 disposed above the roof 422 having a plurality of outlet holes 428 covered from the weather by a conical cap 431. A normally closed valve assembly 434 includes a circular frame 437 which connects upright tube 413 to main air return duct 377. A disk 440 pivotally connected to frame 437 is spring-biased to a closed position which prohibits air to flow through upright tube 413. An electric actuator (not shown) is operatively connected to the disk 440 to move it to an open position wherein air flow is allowed through upright tube 413.

[0046] The outlet duct assembly 335 includes an upright tube 443 which extends from the main air return duct 377 through floor 380, through the upper attic space 416, and extends outwardly from the roof 422. Upright tube 443 includes a capped exhaust air outlet 446 disposed above the roof 422 having a plurality of outlet holes 449 covered from the weather by conical cap 431. A second normally closed valve assembly 452 includes a circular frame 455 which connects upright tube 443 to main air return duct 377. The disk 456 pivotally connected to frame 455 is spring-biased to a closed position which prohibits air to flow through upright tube 443. An electric actuator (not shown) is operatively connected to the disk 456 to move it to an open position wherein air flow is allowed through upright tube 443.

[0047] The bypass air louver valve 336 includes a frame 458 attached along to the main air return duct 377 between the upright tubes 413 and 443, and a plurality of transverse pivoting louvers 461 which are synchronized to pivot together and which are spring-biased to an open position which allows air to flow through the main air return duct 377. An electric actuator (not shown) is operatively connected to the louvers 461 to move them to a closed position wherein air flow from outside of building 329 is allowed into main air return duct 377.

[0048] When a detector 29 senses carbon monoxide at a predetermined level, the alarm signal sent from the particular detector 29 through the associated electrical cable 107 causes control assembly 185 to send the appropriate signals to the HVAC unit 344, inlet air duct assembly 332, the outlet duct assembly 335, the bypass air louver valve 336, warning device 261, and gas shutoff valve 52. These signals cause simultaneous shutting off of the gas flow to the HVAC unit 44 which might be the source of the carbon monoxide, the changing of the air flow within building 26 from that indicated by arrows “D” to that indicated by arrows “E” by reversing the blower 131 of HVAC unit 344 to remove the carbon monoxide from within building 329, and the activation of warning device 261 to warn occupants of the detected carbon monoxide.

[0049] Referring to FIG. 6, therein is shown a sprinkler activation system for the carbon monoxide air exchange systems in accordance with the present invention, designated generally at 464, as installed in the commercial building 26.

[0050] The sprinkler activation system 464 comprises a plurality of sprinkler assemblies 467, 470, 473, 476, 479, 482, and 485 connected to a main water supply pipe 488, each including a water spray nozzle 490 and an electrical solenoid valve 493 disposed along respective water supply pipes 496, 499, 502, 505, 508, 511, and 513 thereof. The solenoid valves 493 are electrically connected to the positive and negative terminals 230 and 233 of the electrical control assembly 185 of any of the air exchange systems 20, 23, and 326, by respective sheathed cables 516 each including a pair of the sprinkler system lead wires 224 and 227.

[0051] When a detector 29 senses carbon monoxide at a predetermined level, or for the case of detectors 29 being smoke detectors sensing smoke, the alarm signal sent from the particular detector 29 through the associated electrical cable 107 causes control assembly 185 to send the appropriate signals to the electrical solenoid valves 493 to open discharging water through spray nozzles 490 to extinguish any fire present. Sprinkler activation system 464 can also be set up to activate the other valves discussed previously.

[0052] Many variations of the carbon monoxide air exchange system of the present invention are possible while staying within the same inventive concept. For example, the air exchange systems may use detectors which measure the level of other gaseous components or conditions of the air other than carbon monoxide, such as heat, smoke, carbon dioxide, other gases, chemicals, etc. Likewise, the air exchange systems may control other sources of carbon monoxide besides HVAC units, such as standard non-HVAC gas furnaces, gas ranges, etc., and sources producing gaseous components or conditions other than carbon monoxide. The air exchange systems may be activated by the use of a device other than a detector, such as a microphone or other sound sensing type of device connected thereto as the detectors are, wherein the air exchange system is activated when the alarm sound from a standard, unmodified carbon monoxide sensing device is picked up by the microphone. The control box may be designed in different sizes to accommodate different systems and locations. The system may also be utilized as a self-contained or portable smoke elimination system. The air exchange system may also be designed with an automatic timing device for automatic shut-down of the system.

[0053] Whereas this invention is here illustrated and described with reference to embodiments thereof presently contemplated as the best mode of carrying out such invention in actual practice, it is to be understood that various changes may be made in adapting the invention to different embodiments without departing from the broader inventive concepts disclosed herein and comprehended by the claims that follow. 

I claim:
 1. An air exchange system for use with a forced air system within a building, the forced air system being of the type having a blower unit which moves air from an inlet to an outlet thereof, an intake duct assembly being connected to the inlet for gathering air from above a floor of the building, and an outlet duct assembly connected to the outlet for distributing the air back throughout the building, the air exchange system which monitors the concentration of at least one gaseous component of air present in the building and removes the gaseous component from the air upon reaching a predetermined threshold concentration, the air exchange system comprising: at least one detector which detects the level of the gaseous component, generating an alarm signal upon the level of the gaseous component reaching the predetermined threshold concentration; an exhausting unit having an upright housing which includes an internal chamber extending therethrough, said housing having an exhaust air inlet disposed above the floor, and an exhaust air outlet adapted to discharge air externally of the building, a blower being operatively associated with said housing for moving air inside the building into said exhaust air inlet and out of the building through said exhaust air outlet; an inlet air duct assembly which includes an inlet air duct having a fresh air inlet adapted to receive fresh air external of the building and a fresh air outlet internal to the building, and a normally closed bypass air valve disposed along said inlet air duct; and an electrical control system operatively connected to each of said detectors for receiving the alarm signal and activating said blower to remove air from within the building opening said bypass air valve to replenish removed air through said inlet air duct with fresh air from outside the building.
 2. The air exchange system according to claim 1, wherein each detector plugs into an electrical wall outlet which powers said detector.
 3. The air exchange system according to claim 1, wherein there are a plurality of detectors each being insulated from the alarm signals of others of said detectors so as not to be triggered thereby.
 4. The air exchange system according to claim 3, wherein the plurality of detectors comprise respective carbon monoxide detectors.
 5. The air exchange system according to claim 1, further comprising at least one electrically actuatable, normally open gas shutoff valve disposed along a gas inlet line feeding gas to an internal combustion device in the building which might be the source of carbon monoxide, said gas shutoff valve being operatively connected to the electrical control system such that when one of the detectors detects the level of a gaseous component associated with combustion and fires in buildings above a predetermined level, the alarm signal sent from said detector causes said electrical control system actuate said gas shutoff valve to a closed position wherein gas is shut off from the internal combustion device which might be the source of the carbon monoxide.
 6. The air exchange system according to claim 1, wherein the alarm signal sent from the detector causes the electrical control system to stop the blower unit from running and moving air therethrough.
 7. The air exchange system according to claim 1, further comprising a sprinkler activation system which includes at least sprinkler assembly connected to a main water supply pipe for receiving pressurized water from a water supply of the building, each sprinkler assembly having a water supply pipe mounted below a ceiling of the building, being connected at one end to the main water supply pipe and a water spray nozzle connected at an opposite end thereof, an electrically actuatable, normally closed water valve being disposed along the water supply pipe to stop water from flowing through said spray nozzle, said valve being operatively connected to the electrical control system such that when one of the detectors detects the level of a gaseous component associated with combustion and fires in buildings above a predetermined level, the alarm signal sent from said detector causes said electrical control system actuate said water valves to an open position wherein water discharges through said spray nozzles to extinguish any fire which may be present thereunder.
 8. An air exchange system for use in buildings to monitor and the concentration of at least one gaseous component of air present in the building, and remove the gaseous component from the air upon reaching a predetermined threshold concentration, comprising: at least one detector which detects the level of the gaseous component, generating an alarm signal upon the level of the gaseous component reaching the predetermined threshold concentration; an exhausting unit having an upright housing which includes an internal chamber extending therethrough, said housing having an exhaust air inlet disposed above the floor, and an exhaust air outlet adapted to discharge air externally of the building, a blower being operatively associated with said housing for moving air inside the building into said exhaust air inlet and out of the building through said exhaust air outlet; an inlet air duct assembly which includes an inlet air duct having a fresh air inlet adapted to receive fresh air external of the building and a fresh air outlet internal to the building, and a normally closed bypass air valve disposed along said inlet air duct; and an electrical control system operatively connected to each of said detectors for receiving the alarm signal and activating said blower to remove air from within the building, and opening said bypass air valve to replenish removed air through said inlet air duct with fresh air from outside the building.
 9. The air exchange system according to claim 8, wherein each detector plugs into an electrical wall outlet which powers said detector.
 10. The air exchange system according to claim 8, wherein there are a plurality of detectors each being insulated from the alarm signals of others of said detectors so as not to be triggered thereby.
 11. The air exchange system according to claim 10, wherein the plurality of detectors comprise respective carbon monoxide detectors.
 12. The air exchange system according to claim 8, further comprising a sprinkler activation system which includes at least sprinkler assembly connected to a main water supply pipe for receiving pressurized water from a water supply of the building, each sprinkler assembly having a water supply pipe mounted below a ceiling of the building, being connected at one end to the main water supply pipe and a water spray nozzle connected at an opposite end thereof, an electrically actuatable, normally closed water valve being disposed along the water supply pipe to stop water from flowing through said spray nozzle, said valve being operatively connected to the electrical control system such that when one of the detectors detects the level of a gaseous component associated with combustion and fires in buildings above a predetermined level, the alarm signal sent from said detector causes said electrical control system actuate said water valves to an open position wherein water discharges through said spray nozzles to extinguish any fire which may be present thereunder.
 13. An air exchange system for use with a forced air system within a building, the forced air system being of the type having a blower unit which moves air from an inlet to an outlet thereof, an intake duct assembly being connected to the inlet for gathering air from the building, and an outlet duct assembly connected to the outlet for distributing the air back throughout the building through a plurality of floor registers disposed closely adjacent a floor thereof, the air exchange system which monitors and the concentration of at least one gaseous component of air present in the building and removes the gaseous component from the air upon reaching a predetermined threshold concentration, the air exchange system comprising: at least one detector which detects the level of the gaseous component, generating an alarm signal upon the level of the gaseous component reaching the predetermined threshold concentration; an inlet air duct assembly includes an inlet air duct having a fresh air inlet adapted to receive fresh air external of the building and a fresh air outlet connected to the intake duct assembly, and a normally closed bypass air valve disposed along said inlet air duct; an outlet duct assembly includes an outlet air duct having an exhaust air inlet for receiving air from within the building and an exhaust air outlet for discharging the air externally of the building; a valve assembly operatively associated with at least one of said an inlet and outlet duct assemblies to normally block fresh air from flowing through said fresh air inlet into the building and air inside the building from flowing out through said outlet air duct to outside of the building; and an electrical control system operatively connected to each of said detectors for receiving the alarm signal and activating reversing the blower and activating said valve assembly from a normally blocked position to a reversed position to reverse the flow of air such that air is drawn from inside the building through the floor registers and blown out through said outlet duct assembly, and fresh air drawn from outside the building through inlet air duct assembly to replenish removed air.
 14. The air exchange system according to claim 13, wherein the valve assembly includes a pair of valves, one operatively associated with the inlet duct assembly to normally block fresh air from flowing through the fresh air inlet into the building, and one operatively associated with the outlet duct assembly to normally block air inside the building from flowing out through the outlet air duct to outside of the building.
 15. The air exchange system according to claim 14, wherein the valve assembly further includes an additional valve operably disposed in the intake duct assembly between the pair of valves, said additional valve being controlled by the electrical control system.
 16. The air exchange system according to claim 13, wherein each detector plugs into an electrical wall outlet which powers said detector.
 17. The air exchange system according to claim 13, wherein there are a plurality of detectors each being insulated from the alarm signals of others of said detectors so as not to be triggered thereby.
 18. The air exchange system according to claim 17, wherein the plurality of detectors comprise respective carbon monoxide detectors.
 19. The air exchange system according to claim 13, further comprising at least one electrically actuatable, normally open gas shutoff valve disposed along a gas inlet line feeding gas to an internal combustion device in the building which might be the source of carbon monoxide, said gas shutoff valve being operatively connected to the electrical control system such that when one of the detectors detects the level of a gaseous component associated with combustion and fires in buildings above a predetermined level, the alarm signal sent from said detector causes said electrical control system actuate said gas shutoff valve to a closed position wherein gas is shut off from the internal combustion device which might be the source of the carbon monoxide.
 20. The air exchange system according to claim 13, further comprising a sprinkler activation system which includes at least sprinkler assembly connected to a main water supply pipe for receiving pressurized water from a water supply of the building, each sprinkler assembly having a water supply pipe mounted below a ceiling of the building, being connected at one end to the main water supply pipe and a water spray nozzle connected at an opposite end thereof, an electrically actuatable, normally closed water valve being disposed along the water supply pipe to stop water from flowing through said spray nozzle, said valve being operatively connected to the electrical control system such that when one of the detectors detects the level of a gaseous component associated with combustion and fires in buildings above a predetermined level, the alarm signal sent from said detector causes said electrical control system actuate said water valves to an open position wherein water discharges through said spray nozzles to extinguish any fire which may be present thereunder. 